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Quantum Entanglement in Heisenberg Antiferromagnets

V. Subrahmanyam
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Abstract

Entanglement sharing among pairs of spins in Heisenberg antiferromagnets is investigated using the concurrence measure. For a nondegenerate S=0 ground state, a simple formula relates the concurrence to the diagonal correlation function. The concurrence length is seen to be extremely short. A few finite clusters are studied numerically, to see the trend in higher dimensions. It is argued that nearest-neighbour concurrence is zero for triangular and Kagome lattices. The concurrences in the maximal-spin states are explicitly calculated, where the concurrence averaged over all pairs is larger than the S=0 states.

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V. Subrahmanyam. 2003-12-24. Quantum Entanglement in Heisenberg Antiferromagnets. https://doi.org/10.1103/physreva.69.022311

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